/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.io;

import java.io.*;

/**
 * This class can read a given file or directory, recursively, applying a given DataEntryReader to all files it comes
 * across.
 *
 * @author Eric Lafortune
 */
public class DirectoryPump implements DataEntryPump {
    private final File directory;

    public DirectoryPump(File directory) {
        this.directory = directory;
    }

    // Implementations for DataEntryPump.

    public void pumpDataEntries(DataEntryReader dataEntryReader) throws IOException {
        if (!directory.exists()) {
            throw new IOException("No such file or directory: " + directory);
        }

        readFiles(directory, dataEntryReader);
    }

    /**
     * Reads the given subdirectory recursively, applying the given DataEntryReader to all files that are encountered.
     */
    private void readFiles(File file, DataEntryReader dataEntryReader) throws IOException {
        // Pass the file data entry to the reader.
        dataEntryReader.read(new FileDataEntry(directory, file));

        if (file.isDirectory()) {
            // Recurse into the subdirectory.
            File[] listedFiles = file.listFiles();

            for (int index = 0; index < listedFiles.length; index++) {
                File listedFile = listedFiles[index];
                try {
                    readFiles(listedFile, dataEntryReader);
                } catch (IOException e) {
                    throw new IOException("Can't read [" + listedFile.getName() + "] (" + e.getMessage() + ")", e);
                }
            }
        }
    }
}
